Add scheme to URL if needed
Interestingly, although Uri
and UriBuilder
completely mangle any url without a scheme, WebProxy
does it right.
So just call:
new WebProxy(proxy.ProxyServer).Address
You could also use UriBuilder
:
public static Uri GetUri(this string s)
{
return new UriBuilder(s).Uri;
}
Remarks from MSDN:
This constructor initializes a new instance of the UriBuilder class with the Fragment, Host, Path, Port, Query, Scheme, and Uri properties set as specified in uri.
If uri does not specify a scheme, the scheme defaults to "http:".
If you just want to add the scheme, without validating the URL, the fastest/easiest way is to use string lookups, eg:
string url = "mydomain.com";
if (!url.StartsWith("http://", StringComparison.OrdinalIgnoreCase)) url = "http://" + url;
A better approach would be to use Uri
to also validate the URL using the TryCreate
method:
string url = "mydomain.com";
Uri uri;
if ((Uri.TryCreate(url, UriKind.Absolute, out uri) || Uri.TryCreate("http://" + url, UriKind.Absolute, out uri)) &&
(uri.Scheme == Uri.UriSchemeHttp || uri.Scheme == Uri.UriSchemeHttps))
{
// Use validated URI here
}
As @JanDavidNarkiewicz pointed out in the comments, validating the Scheme
is necessary to guard against invalid schemes when a port is specified without scheme, e.g. mydomain.com:80
.
My solution was for protocall-less urls to make sure they have protocal was regex :
Regex.Replace(s, @"^\/\/", "http://");